Households in Wales received both English language and Welsh language questionnaires, and information leaflets.

Householders could complete their questionnaire and return it by post or they could complete the census questionnaire online. Each paper questionnaire had an internet access code which was unique to that household which enabled the householder to complete their questionnaire online.

Questionnaires returned via the post, or through the internet, were receipted daily and this information uploaded onto the questionnaire tracking (QT) system. This enabled the identification of households for follow-up where a questionnaire had not been returned or completed online.

Communal establishments, for example, managed accommodation (such as care homes) and special groups (such as travellers) had their census questionnaires hand delivered.

In communal establishments, questionnaires were collected by the special enumerators and transferred to the census processing site via the census coordinators. Individuals within communal establishments also had the option of completing their questionnaire online following the same process as that used by households.

2011 Census questions

There were 56 questions on the 2011 Census questionnaire: 14 about the household and its accommodation and 42 for each member of the household. For those living in Wales, there was a Welsh and English version of the questionnaire, and an extra question about the Welsh language.

Questions included those about work, health, national identity, passports held, ethnic background, education, second homes, language, religion and marital status.